3.4.4.10 DDR3PHY Data Byte Common Configuration Register
| Name: | DDR3PHY_DXCCR |
| Offset: | 0x28 |
| Reset: | 0x00000800 |
| Property: | Read/Write |
| Bit | 31 | 30 | 29 | 28 | 27 | 26 | 25 | 24 | |
| Access | |||||||||
| Reset |
| Bit | 23 | 22 | 21 | 20 | 19 | 18 | 17 | 16 | |
| AWDT | |||||||||
| Access | R/W | ||||||||
| Reset | 0 |
| Bit | 15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | |
| RVSEL | DQSNRST | DQSNRES[3:0] | |||||||
| Access | R/W | R/W | R/W | R/W | R/W | R/W | |||
| Reset | 0 | 0 | 1 | 0 | 0 | 0 | |||
| Bit | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 | |
| DQSRES[3:0] | DXPDR | DXPDD | DXIOM | DXODT | |||||
| Access | R/W | R/W | R/W | R/W | R/W | R/W | R/W | R/W | |
| Reset | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | |
Bit 16 – AWDT Active Window Data Train
Bit 15 – RVSEL ITMD Read Valid Select
| Value | Description |
|---|---|
| 0 | ITMD read valid signal is generated by delayed DFI read enable signal. |
| 1 | ITMD read valid is generated by the ITMD itseld using asynchronous crossing. |
Bit 14 – DQSNRST DDR_DQSN Reset
Bits 11:8 – DQSNRES[3:0] DDR_DQSN Resistor
Note: DDR_DQSN resistor must be
connected for LPDDR2.
Bits 7:4 – DQSRES[3:0] DDR_DQS Resistor
Note: DDR_DQS resistor must be
connected for LPDDR2.
Selects the on-die pull-down/pull-up resistor for DDR_DQS pins.
DQSRES[3] selects pull-down (when set to '0') or pull-up (when set to '1').
DQSRES[2:0] selects the resistor value as follows:
| Value | Description |
|---|---|
| 0 | Open: On-die resistor disconnected |
| 1 | 688 ohms |
| 2 | 611 ohms |
| 3 | 550 ohms |
| 4 | 500 ohms (recommended value) |
| 5 | 458 ohms |
| 6 | 393 ohms |
| 7 | 344 ohms |
